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31.
Alloy materials such as Si and Ge are attractive as high‐capacity anodes for rechargeable batteries, but such anodes undergo severe capacity degradation during discharge–charge processes. Compared to the over‐emphasized efforts on the electrode structure design to mitigate the volume changes, understanding and engineering of the solid‐electrolyte interphase (SEI) are significantly lacking. This work demonstrates that modifying the surface of alloy‐based anode materials by building an ultraconformal layer of Sb can significantly enhance their structural and interfacial stability during cycling. Combined experimental and theoretical studies consistently reveal that the ultraconformal Sb layer is dynamically converted to Li3Sb during cycling, which can selectively adsorb and catalytically decompose electrolyte additives to form a robust, thin, and dense LiF‐dominated SEI, and simultaneously restrain the decomposition of electrolyte solvents. Hence, the Sb‐coated porous Ge electrode delivers much higher initial Coulombic efficiency of 85% and higher reversible capacity of 1046 mAh g?1 after 200 cycles at 500 mA g?1, compared to only 72% and 170 mAh g?1 for bare porous Ge. The present finding has indicated that tailoring surface structures of electrode materials is an appealing approach to construct a robust SEI and achieve long‐term cycling stability for alloy‐based anode materials.  相似文献   
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Despite their high theoretical energy density and low cost, lithium–sulfur batteries (LSBs) suffer from poor cycle life and low energy efficiency owing to the polysulfides shuttle and the electronic insulating nature of sulfur. Conductivity and polarity are two critical parameters for the search of optimal sulfur host materials. However, their role in immobilizing polysulfides and enhancing redox kinetics for long‐life LSBs are not fully understood. This work has conducted an evaluation on the role of polarity over conductivity by using a polar but nonconductive platelet ordered mesoporous silica (pOMS) and its replica platelet ordered mesoporous carbon (pOMC), which is conductive but nonpolar. It is found that the polar pOMS/S cathode with a sulfur mass fraction of 80 wt% demonstrates outstanding long‐term cycle stability for 2000 cycles even at a high current density of 2C. Furthermore, the pOMS/S cathode with a high sulfur loading of 6.5 mg cm?2 illustrates high areal and volumetric capacities with high capacity retention. Complementary physical and electrochemical probes clearly show that surface polarity and structure are more dominant factors for sulfur utilization efficiency and long‐life, while the conductivity can be compensated by the conductive agent involved as a required electrode material during electrode preparation. The present findings shed new light on the design principles of sulfur hosts towards long‐life and highly efficient LSBs.  相似文献   
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Zhang  Ziyi  Tang  Shengjie  Gui  Weiwei  Lin  Xihua  Zheng  Fenping  Wu  Fang  Li  Hong 《Journal of physiology and biochemistry》2020,76(2):317-328

Podocyte injury plays a key role in the occurrence and development of kidney diseases. Decreased autophagic activity in podocyte is closely related to its injury and the occurrence of proteinuria. Liver X receptors (LXRs), as metabolic nuclear receptors, participate in multiple pathophysiological processes and express in several tissues, including podocytes. Although the functional roles of LXRs in the liver, adipose tissue and intestine are well established; however, the effect of LXRs on podocytes function remains unclear. In this study, we used mouse podocytes cell line to investigate the effects of LXR activation on podocytes autophagy level and related signaling pathway by performing Western blotting, RT-PCR, GFP-mRFP-LC3 transfection, and immunofluorescence staining. Then, we tested this effect in STZ-induced diabetic mice. Transmission electron microscopy and immunohistochemistry were employed to explore the effects of LXR activation on podocytes function and autophagic activity. We found that LXR activation could inhibit autophagic flux through blocking the formation of autophagosome in podocytes in vitro which was possibly achieved by affecting AMPK, mTOR, and SIRT1 signaling pathways. Furthermore, LXR activation in vivo induced autophagy suppression in glomeruli, leading to aggravated podocyte injury. In summary, our findings indicated that activation of LXRs induced autophagy suppression, which in turn contributed to the podocyte injury.

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Reactivation of the androgen receptor signaling pathway in the emasculated environment is the main reason for the occurrence of castration-resistant prostate cancer (CRPC). The immunophilin FKBP51, as a co-chaperone protein, together with Hsp90 help the correct folding of AR. Rapamycin is a known small-molecule inhibitor of FKBP51, but its effect on the FKBP51/AR signaling pathway is not clear. In this study, the interaction mechanism between FKBP51 and rapamycin was investigated using steady-state fluorescence quenching, X-ray crystallization, MTT assay, and qRT-PCR. Steady-state fluorescence quenching assay showed that rapamycin could interact with FKBP51. The crystal of the rapamycin-FKBP51 complex indicated that rapamycin occupies the hydrophobic binding pocket of FK1 domain which is vital for AR activity. The residues involving rapamycin binding are mainly hydrophobic and may overlap with the AR interaction site. Further assays showed that rapamycin could inhibit the androgen-dependent growth of human prostate cancer cells by down-regulating the expression levels of AR activated downstream genes. Taken together, our study demonstrates that rapamycin suppresses AR signaling pathway by interfering with the interaction between AR and FKBP51. The results of this study not only can provide useful information about the interaction mechanism between rapamycin and FKBP51, but also can provide new clues for the treatment of prostate cancer and castration-resistant prostate cancer.  相似文献   
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ObjectivesCutaneous wound healing is one of the major medical problems worldwide. Epigenetic modifiers have been identified as important players in skin development, homeostasis and wound repair. SET domain–containing 2 (SETD2) is the only known histone H3K36 tri‐methylase; however, its role in skin wound healing remains unclear.Materials and MethodsTo elucidate the biological role of SETD2 in wound healing, conditional gene targeting was used to generate epidermis‐specific Setd2‐deficient mice. Wound‐healing experiments were performed on the backs of mice, and injured skin tissues were collected and analysed by haematoxylin and eosin (H&E) and immunohistochemical staining. In vitro, CCK8 and scratch wound‐healing assays were performed on Setd2‐knockdown and Setd2‐overexpression human immortalized keratinocyte cell line (HaCaT). In addition, RNA‐seq and H3K36me3 ChIP‐seq analyses were performed to identify the dysregulated genes modulated by SETD2. Finally, the results were validated in functional rescue experiments using AKT and mTOR inhibitors (MK2206 and rapamycin).ResultsEpidermis‐specific Setd2‐deficient mice were successfully established, and SETD2 deficiency resulted in accelerated re‐epithelialization during cutaneous wound healing by promoting keratinocyte proliferation and migration. Furthermore, the loss of SETD2 enhanced the scratch closure and proliferation of keratinocytes in vitro. Mechanistically, the deletion of Setd2 resulted in the activation of AKT/mTOR signalling pathway, while the pharmacological inhibition of AKT and mTOR with MK2206 and rapamycin, respectively, delayed wound closure.ConclusionsOur results showed that SETD2 loss promoted cutaneous wound healing via the activation of AKT/mTOR signalling.  相似文献   
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利用MISA软件对密花香薷转录组42 362条Unigene进行SSR位点搜索,并对其SSR序列结构及分布特征进行了分析。结果表明:(1)密花香薷转录组Unigene序列中共检测到17 564个SSR重复序列,分布于11 903条Unigene上,出现频率为28.10%,平均每3 200 bp出现一个SSR位点。(2)单、二、三核苷酸重复类型为密花香薷转录组SSR位点的主导基序类型,占总SSR位点的97.27%,3种主导基序类型中,单核苷酸所形成基元类型数量最多,共检测到169个基元类型(51.22%),单核苷酸(A/T)n基元类型占明显优势,二核苷酸重复类型(AG/CT)n基元类型占优,分别占总SSR位点的50.60%和12.17%。(3)单核苷酸SSR位点所包含重复次数最多(49),重复次数介于10~66,同一基序类型不同重复次数所形成的SSR位点数量差异较大,随重复次数的增加,SSR位点数呈下降趋势。(4)密花香薷转录组二至六核苷酸基序SSR序列长度集中在12~30 bp区间,共包含有8 190个SSR位点,占所统计SSR位点的95.60%,1 589 (≥20 bp)个SSR序列具有极高的多态性,占所统计SSR位点的18.54%。综合出现频率、分布密度、基元重复次数和长度变异等多个研究结果发现,密花香薷转录组检索到的SSR序列表现出较高的多态性潜能,具有较大的开发价值。该研究为后续密花香薷SSR分子标记引物开发奠定了理论基础。  相似文献   
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The goal of this article is to contribute to the understanding of how the multiple, and sometimes conflicting, stakeholder perspectives and prevailing conditions (economic, geographic, etc.) in the implementation locality shape extended producer responsibility (EPR) “on the ground.” We provide an in‐depth examination of the implementation dimension of EPR in a specific case study by examining concrete activities at the operational front of the collection and recycling system, and probing the varying stakeholder preferences that have driven a specific system to its status quo. To this end, we conduct a detailed case study of the Washington State EPR implementation for electronic waste. We provide an overview of various stakeholder perspectives and their implications for the attainment of EPR policy objectives in practice. These findings shed light on the intrinsic complexity of EPR implementation. We conclude with recommendations on how to achieve effective and efficient EPR implementation, including improving design incentives, incorporating reuse and refurbishing, expanding product scope, managing downstream material flows, and promoting operational efficiency via fair cost allocation design.  相似文献   
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